mybatis的模糊查询写法

mybatis做like模糊查询

 

1.  参数中直接加入%%

　　param.setUsername("%CD%");
      param.setPassword("%11%");

	<select  id="selectPersons" resultType="person" parameterType="person">
		select id,sex,age,username,password from person where true 
			<if test="username!=null"> AND username LIKE #{username}</if>
			<if test="password!=null">AND password LIKE #{password}</if>
	
	</select>

2.  bind标签

<select id="selectPersons" resultType="person" parameterType="person">
  <bind name="pattern" value="'%' + _parameter.username + '%'" />
  select id,sex,age,username,password 
  from person
  where username LIKE #{pattern}
</select>

3. CONCAT

where username LIKE concat(concat('%',#{username}),'%')

模糊查询：

工作中用到，写三种用法吧，第四种为大小写匹配查询

1. sql中字符串拼接

   SELECT * FROM tableName WHERE name LIKE CONCAT(CONCAT('%', #{text}), '%');

2. 使用 ${...} 代替 #{...}

   SELECT * FROM tableName WHERE name LIKE '%${text}%'; 

3. 程序中拼接

   Java

   // or String searchText = "%" + text + "%";

   String searchText = new StringBuilder("%").append(text).append("%").toString();

   parameterMap.put("text", searchText);

   SqlMap.xml

   SELECT * FROM tableName WHERE name LIKE #{text};

4. 大小写匹配查询

SELECT *  FROM TABLENAME  WHERE UPPER(SUBSYSTEM) LIKE '%' || UPPER('jz') || '%'
 --或者是
SELECT *   FROM TABLENAME  WHERE LOWER(SUBSYSTEM) LIKE '%' || LOWER('jz') || '%'

 

异常：

java.lang.IllegalArgumentException: modify is ambiguous in Mapped Statements collection (try using the full name including the namespace, or rename one of the entries)
 at org.apache.ibatis.session.Configuration$StrictMap.get(Configuration.java:466)
 at org.apache.ibatis.session.Configuration.getMappedStatement(Configuration.java:349)
 at org.apache.ibatis.binding.MapperMethod.setupCommandType(MapperMethod.java:137)
 at org.apache.ibatis.binding.MapperMethod.<init>(MapperMethod.java:46)
 at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:34)
 at $Proxy10.modify(Unknown Source)

抛出这个异常的原因可能是因为mapper.xml配置文件中<mapper>的namespace属性配置错误造成的，没有根据命名空间的值（全称类名）找到相应映射接口。

如：<mapper namespace="com.xxx.xxx.mapper.TestMapper" >